As for the process for producing a β-ketonitrile compound by reacting an aliphatic carboxylic acid ester compound in the presence of a metal alkoxide, J. Am. Chem. Soc., 56, 1171 (1934) discloses a reaction between ethyl isobutylate and acetonitrile in the presence of sodium ethoxide, and Japanese Patent Provisional Publication No. 6-312966 discloses a reaction between an acetic acid ester and acetonitile in the presence of an alkali alcolate.
According to the study performed by the present inventors, it has been revealed that the reactions disclosed in the prior art publications yield by-products such as 3-oxybutyronitrile and compounds having pyrimidine nucleus in addition to the desired product of β-ketonitrile compound. Thus, the known processes could not yield the β-ketonitrile compound of a high purity in a good yield.
It is an object of the present invention to provide an industrially applicable process for producing a β-ketonitrile compound of high purity in a good yield from an easily available aliphatic carboxylic acid ester compound.